/* Copyright 2018 Mozilla Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import { buildGetDocumentParams } from "./test_utils.js";
import { EventBus } from "../../web/ui_utils.js";
import { getDocument } from "../../src/display/api.js";
import { PDFFindController } from "../../web/pdf_find_controller.js";
import { SimpleLinkService } from "../../web/pdf_link_service.js";

const tracemonkeyFileName = "tracemonkey.pdf";

class MockLinkService extends SimpleLinkService {
  constructor() {
    super();

    this._page = 1;
    this._pdfDocument = null;
  }

  setDocument(pdfDocument) {
    this._pdfDocument = pdfDocument;
  }

  get pagesCount() {
    return this._pdfDocument.numPages;
  }

  get page() {
    return this._page;
  }

  set page(value) {
    this._page = value;
  }
}

async function initPdfFindController(filename) {
  const loadingTask = getDocument(
    buildGetDocumentParams(filename || tracemonkeyFileName)
  );
  const pdfDocument = await loadingTask.promise;

  const eventBus = new EventBus();

  const linkService = new MockLinkService();
  linkService.setDocument(pdfDocument);

  const pdfFindController = new PDFFindController({
    linkService,
    eventBus,
  });
  pdfFindController.setDocument(pdfDocument); // Enable searching.

  return { eventBus, pdfFindController };
}

function testSearch({
  eventBus,
  pdfFindController,
  state,
  matchesPerPage,
  selectedMatch,
  pageMatches = null,
  pageMatchesLength = null,
}) {
  return new Promise(function (resolve) {
    const eventState = Object.assign(
      Object.create(null),
      {
        source: this,
        type: "",
        query: null,
        caseSensitive: false,
        entireWord: false,
        phraseSearch: true,
        findPrevious: false,
      },
      state
    );
    eventBus.dispatch("find", eventState);

    // The `updatefindmatchescount` event is only emitted if the page contains
    // at least one match for the query, so the last non-zero item in the
    // matches per page array corresponds to the page for which the final
    // `updatefindmatchescount` event is emitted. If this happens, we know
    // that any subsequent pages won't trigger the event anymore and we
    // can start comparing the matches per page. This logic is necessary
    // because we call the `pdfFindController.pageMatches` getter directly
    // after receiving the event and the underlying `_pageMatches` array
    // is only extended when a page is processed, so it will only contain
    // entries for the pages processed until the time when the final event
    // was emitted.
    let totalPages = matchesPerPage.length;
    for (let i = totalPages - 1; i >= 0; i--) {
      if (matchesPerPage[i] > 0) {
        totalPages = i + 1;
        break;
      }
    }

    const totalMatches = matchesPerPage.reduce((a, b) => {
      return a + b;
    });

    eventBus.on(
      "updatefindmatchescount",
      function onUpdateFindMatchesCount(evt) {
        if (pdfFindController.pageMatches.length !== totalPages) {
          return;
        }
        eventBus.off("updatefindmatchescount", onUpdateFindMatchesCount);

        expect(evt.matchesCount.total).toBe(totalMatches);
        for (let i = 0; i < totalPages; i++) {
          expect(pdfFindController.pageMatches[i].length).toEqual(
            matchesPerPage[i]
          );
        }
        expect(pdfFindController.selected.pageIdx).toEqual(
          selectedMatch.pageIndex
        );
        expect(pdfFindController.selected.matchIdx).toEqual(
          selectedMatch.matchIndex
        );

        if (pageMatches) {
          expect(pdfFindController.pageMatches).toEqual(pageMatches);
          expect(pdfFindController.pageMatchesLength).toEqual(
            pageMatchesLength
          );
        }

        resolve();
      }
    );
  });
}

describe("pdf_find_controller", function () {
  it("performs a normal search", async function () {
    const { eventBus, pdfFindController } = await initPdfFindController();

    await testSearch({
      eventBus,
      pdfFindController,
      state: {
        query: "Dynamic",
      },
      matchesPerPage: [11, 5, 0, 3, 0, 0, 0, 1, 1, 1, 0, 3, 4, 4],
      selectedMatch: {
        pageIndex: 0,
        matchIndex: 0,
      },
    });
  });

  it("performs a normal search and finds the previous result", async function () {
    // Page 14 (with page index 13) contains five results. By default, the
    // first result (match index 0) is selected, so the previous result
    // should be the fifth result (match index 4).
    const { eventBus, pdfFindController } = await initPdfFindController();

    await testSearch({
      eventBus,
      pdfFindController,
      state: {
        query: "conference",
        findPrevious: true,
      },
      matchesPerPage: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 5],
      selectedMatch: {
        pageIndex: 13,
        matchIndex: 4,
      },
    });
  });

  it("performs a case sensitive search", async function () {
    const { eventBus, pdfFindController } = await initPdfFindController();

    await testSearch({
      eventBus,
      pdfFindController,
      state: {
        query: "Dynamic",
        caseSensitive: true,
      },
      matchesPerPage: [3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 3],
      selectedMatch: {
        pageIndex: 0,
        matchIndex: 0,
      },
    });
  });

  it("performs an entire word search", async function () {
    // Page 13 contains both 'Government' and 'Governmental', so the latter
    // should not be found with entire word search.
    const { eventBus, pdfFindController } = await initPdfFindController();

    await testSearch({
      eventBus,
      pdfFindController,
      state: {
        query: "Government",
        entireWord: true,
      },
      matchesPerPage: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0],
      selectedMatch: {
        pageIndex: 12,
        matchIndex: 0,
      },
    });
  });

  it("performs a multiple term (no phrase) search", async function () {
    // Page 9 contains 'alternate' and pages 6 and 9 contain 'solution'.
    // Both should be found for multiple term (no phrase) search.
    const { eventBus, pdfFindController } = await initPdfFindController();

    await testSearch({
      eventBus,
      pdfFindController,
      state: {
        query: "alternate solution",
        phraseSearch: false,
      },
      matchesPerPage: [0, 0, 0, 0, 0, 1, 0, 0, 4, 0, 0, 0, 0, 0],
      selectedMatch: {
        pageIndex: 5,
        matchIndex: 0,
      },
    });
  });

  it("performs a normal search, where the text is normalized", async function () {
    const { eventBus, pdfFindController } = await initPdfFindController(
      "fraction-highlight.pdf"
    );

    await testSearch({
      eventBus,
      pdfFindController,
      state: {
        query: "fraction",
      },
      matchesPerPage: [3],
      selectedMatch: {
        pageIndex: 0,
        matchIndex: 0,
      },
      pageMatches: [[19, 46, 62]],
      pageMatchesLength: [[8, 8, 8]],
    });
  });
});
